﻿using System;

class MyMath
{

    public static double Add(double x, double y)
    {
        return x + y;
    }
    public static double Subtract(double x, double y)
    {
        return x - y;
    }
    public static double Multiply(double x, double y)
    {
        return x * y;
    }
    public static double Divide(double x, double y)
    {
        return x / y;
    }
}
class Program
{
    static void Main(string[] args)
    {
        Console.Write("请输入两个数字: ");
        double x = Convert.ToDouble(Console.ReadLine());
        double y = Convert.ToDouble(Console.ReadLine());

        Console.WriteLine($"加：{x} + {y} = {MyMath.Add(x, y)}");
        Console.WriteLine($"减：{x} - {y} = {MyMath.Subtract(x, y)}");
        Console.WriteLine($"乘：{x} * {y} = {MyMath.Multiply(x, y)}");
        Console.WriteLine($"除：{x} / {y} = {MyMath.Divide(x, y)}");
    }
}